Anyone Successfully Go from Floor Standers to Bookshelf Monitors w/ Subs?

My system is in a Large Living room which opens to dining room & Kitchen. I figure about 6k cu ft. I have Silverline Sonata speakers now with subs. Unfortunately I did not build my addition when I should have 10-15 yrs ago. Now I'm not really up to the task. Too old & wore out. So I'd love to make the LR a prettier room for my wife. One thing we talked about was the large speakers, and possibly using Watkins Gen 4 monitors. But as good as they sound, I am concerned about the ability to fill the room, or at least my listening area. As I understand, it is about moving air. I cannot see how a 6.5 & 1 inch speaker can move as much as a 10, 7, 3 & 1 inch. So I am quite concerned about that. Right now, the system sounds very pleasing to both of us. We don't want to take a backward step but can live with a sideways step if it is more visually pleasing.

Has anyone made this kind of a step from floor standers to monitors, both with subs, in a large room, with success? Or am I thinking correctly about the small speakers inability to move the proper amount of air for the room size? Thanks for your help.

OH, FWIW, The addition may not be completely out of the picture. But it depends on whether I can get one of my previous sub contractors to do a large part of it.